A picture of North Korea's Kim Jong-Un with a smartphone has triggered fevered speculation about which brand is favoured by the leader of one of the world's most repressive nations.

The photo released by the North's state media showed Mr Kim presiding over a meeting with top national security advisers last week - a meeting believed to have been focused on Pyongyang's threat to conduct an imminent nuclear test.

It also showed a black smartphone on the table next to Kim's arm, as well as a lit cigarette in his hand.

"It's believed that the smartphone belonged to Kim given that the device was placed right next to the documents he was looking at," a Seoul government official said.

The South Korean media gave the picture prominent coverage, opening a debate over the manufacturer, with speculation ranging between South Korea's own Samsung, Taiwan's HTC and iPhone maker Apple.

Samsung, the world's top smartphone maker, was adamant that one of its flagship Galaxy models had not turned up across the border.

"It's not a Samsung phone," a company spokesman said.

The Seoul government official said the picture had been analysed by the South's intelligence agency, which concluded that HTC was the likely manufacturer.

The Taiwanese firm declined to identify the device but said in a statement that the company appreciated the "support of all users".

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